Regenerated collagen fibers, which are composed of proteins, are similar to human hair in composition and have a soft texture (touch), and hence they have been proposed conventionally as fibers for artificial hair (Patent Documents 1 to 3). In order to make regenerated collagen fibers more similar to human hair, they preferably have an elliptical shape in cross section.
However, regenerated collagen fibers have a problem in that they are too high in gloss, which leads to an undesirable poor appearance. In particular, regenerated collagen fibers having an elliptical shape in cross section are more likely to show this tendency. A hair product with a high gloss fiber, as compared with that of human hair or the like, produces a feeling of strangeness sense of artificiality, resulting in a low reduced commercial value for the product.